nRF7002-DK Powering-off WiFi companion

[BENBF]

Hello,

As working on the nRF7002-DK, I wanted to power off the nRF7002 in order to reduce power consumption.
What I wanted to do was : Start application -> Connect to WiFi -> Send data using TCP -> power off nRF7002 -> Wait -> power on nRF7002 -> Connect to WiFi .....

For this, I wanted to disable BUCK_EN and nRF7002_IOVDD_EN unfortunately i can't add those pins to my .overlay file in my project as they don't seem to have a compatible properties in the nordic,nrf7002.yaml in  nrf/dts/binding/wifi hence I can't find a way to define an alias for those pin.

Do anyone have an idea of how I could achieve controlling those pins or have another way to perform the sequence I'm trying to implement ?

Thanks,
Best regards

[Håkon Alseth]

Hi,

 

What I wanted to do was : Start application -> Connect to WiFi -> Send data using TCP -> power off nRF7002 -> Wait -> power on nRF7002 -> Connect to WiFi .....

Unfortunately, there is a restriction in the net subsys of zephyr that you cannot re-init at this time.

You will have to reset the host controller (nRF5340) to power up the nRF7002 again after placing it in power off.

 

This is how you control these two GPIOs:

https://github.com/nrfconnect/sdk-nrf/blob/v2.4.0/drivers/wifi/nrf700x/zephyr/src/qspi/src/rpu_hw_if.c#L32-L36

https://github.com/nrfconnect/sdk-nrf/blob/v2.4.0/drivers/wifi/nrf700x/zephyr/src/qspi/src/rpu_hw_if.c#L354-L355

 

For this, I wanted to disable BUCK_EN and nRF7002_IOVDD_EN unfortunately i can't add those pins to my .overlay file in my project as they don't seem to have a compatible properties in the nordic,nrf7002.yaml in  nrf/dts/binding/wifi hence I can't find a way to define an alias for those pin.

They are most likely already declared in the qspi DT:

https://github.com/nrfconnect/sdk-nrf/blob/v2.4.0/boards/arm/nrf7002dk_nrf5340/nrf5340_cpuapp_common.dts#L200-L201

 

Note that you can copy the C identifier if you're using our plugins:

https://github.com/NordicPlayground/vscode-nrf-devicetree#copy-c-identifiers

 

Kind regards,

Håkon

[BENBF]

Hello Håkon,

Thank you for your reply.

I guess I'll try to put the nRF7002 in sleep mode for now.

Best regards

[Håkon Alseth]

I just wanted to let you know;

I have inputted this as a feature request internally, so hopefully placing the nRF7002 in the deepest sleep mode will be more seamless and user-friendly in the future.

 

Kind regards,

Håkon

[Ioannis]

IIUC, this behavior is now partially demonstrated in nRF Connect SDK "Wi-Fi Shutdown" sample https://github.com/nrfconnect/sdk-nrf/tree/main/samples/wifi/shutdown

[BENBF]

Hello again, I have been experimenting with what you advised.

Using the shutdown example (github.com/.../shutdown), I did not succeed in saving power as it does not change the nRF7002 voltage.

I then used rpu_disable() and rpu_enable() thanks to the link you provided me with. It did turn off and turn on the nRF7002, but when turning off the nRF7002, I am presented with the following messages:

[00:00:11.630,096] <err> wifi_nrf: hal_rpu_mem_write: Invalid memory address 0x88888888
[00:00:11.630,157] <err> wifi_nrf: hal_rpu_msg_write: Copying information to RPU failed
[00:00:11.630,187] <err> wifi_nrf: hal_rpu_cmd_process_queue: Writing command to RPU failed
[00:00:11.630,615] <err> wifi_nrf: hal_rpu_mem_write: Invalid memory address 0x88888888
[00:00:11.630,645] <err> wifi_nrf: hal_rpu_msg_write: Copying information to RPU failed
[00:00:11.630,676] <err> wifi_nrf: hal_rpu_cmd_process_queue: Writing command to RPU failed
[00:00:11.631,103] <err> wifi_nrf: hal_rpu_mem_write: Invalid memory address 0x88888888
[00:00:11.631,164] <err> wifi_nrf: hal_rpu_msg_write: Copying information to RPU failed
[00:00:11.631,195] <err> wifi_nrf: hal_rpu_cmd_process_queue: Writing command to RPU failed
[00:00:11.631,225] <err> wifi_nrf: wifi_nrf_wpa_set_supp_port: wifi_nrf_fmac_chg_sta failed

And when turned on, I cannot interact with the nRF7002 again. Do you have any idea about how to re-enable the nRF7002 connection without resetting both the nRF7002 and nRF5340?

Thank you for your help, and have a good day.